What is Power Factor Correction (PFC)? By defention Power factor correction (PFC) is a technique or method of counteracting the undesirable effects of electric loads that create a power factor that is less than one. Power factor correction may be applied either by an electrical power current transmission utility to improve the stability, integrety, and efficiency of the transmission network; or, a correction may be installed by individual electrical customers to reduce the costs charged to them by their electricity supplier.
Power Factor Correction (PFC) in ATX PC Power Supplies Power Factor Correction (PFC) allows power distribution to operate at its maximum ENERGY efficiency. There are two types of PFC, Active PFC and Passive PFC. Computer power supplies are either Active PFC Power Supplies or Passive PFC Power Supplies. All our Quiet PC Power supplies rated 500 watts and over are Active PFC and 80 PLUS Certified. Active PFC handsdown is the most best effective method and can produce a PFC of 0.99 (99%).
Active PFC An Active Power Factor Corrector (active PFC) is a power electronic system that controls the amount of power drawn by a load in order to obtain a the cleanest Power factor as possible to unity. In most applications, the active PFC controls the input current of the load so that the current waveform is proportional to the mains voltage waveform (a sinewave).
Some types of active PFC are
Boost
Buck
Buck-boost
Active power factor correctors can be single-stage or multi-stage.
Active PFC is the most effective and can produce a PFC of 0.99 (99%).
The preferable type of PFC being the Active Power Factor Correction (Active PFC) since it provides more efficient power frequency. Because Active PFC uses a circuit to correct power factor, Active PFC is able to generate a theoretical power factor of well over 95%. in high quality PC power supplies like Zalman. Active Power Factor Correction also markedly diminishes total harmonics, automatically corrects for AC input voltage, and is capable of a full range of input voltage. Since Active PFC is the more complex method of Power Factor Correction, it is more expensive to produce an energy efficient Active PFC PC power supply but in the long run it will sabe you more on energy therefor lowere electrical bills .
Like evry thing ealse there are better made Active PFC power supplies. These are 80 PLUS certified Active PFC and carry the 80 PLUS Logo.
What does 80 PLUS Mean? Power supplies that are 80 PLUS certified use only as much electricity as is being requested by the computer. For example, if a computer has an 80 PLUS PSU rated at 650 watts but the computer only requires 300 watts to run then the PSU will only output 300watts of electricity. 80% or more of the electricity drawn from the electrial socket is converted to DC for use in the computer. In a conventional PSU, especially generic or lesser known brands, lots of electricity is wasted due to heat and conversion. A conventional 650watt PSU may draw 500watts to power a 300watt computer, the remaining 200watts is lost as heat.
The PSU which is responsible for powering all a computers components is now one of the more efficient components in a modern computer. The reduction of energy, heat, and noise pollution has lowered the carbon footprint for computers and caused millions in energy savings.
Passive PFC The most common type of PFC is Passive Power Factor Correction (Passive PFC). This is a simple way of correcting the nonlinearity of a power load by using capacitor banks. It is not as effective as an Active PFC. and is not an 80 PLUS Standard. By Switching the capacitors into or out of the circuit causes harmonics, which is why Active PFC or a synchronous motor is preferred. Only older Power supply Units (PSU) or new poor quality less expensive units use thsi type of power correction method now a days. Another problem with Passive PFC IS IT uses a capacitive filter at the AC input to correct poor power factor. Passive PFC may be affected when environmental vibration occurs. Passive PFC requires that the AC input voltage be set manually. Passive PFC also does not use the full energy potential of the AC line therfore resulting in a poor power distribution.
Non-PFC Non-PFC PC power supplies are no longer recommended. In Europe, or the USA power supplies are now required to have either active PFC or passive PFC and meet certain critiria.
Acoustic PC Acoustic PC Offers the latest and best fo class ATX PC Power Supplies available with active PFC and 80 PLUS Energy Efficency Certified as well as RoHS Compliant . Make sure to viist our Quiet PC power supply link to our wide selection.
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